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Homework Help: Help with Static Equilibrium question

  1. Sep 24, 2006 #1
    If anyone can help me out, i'd really appreciate it. I'm not necessarily looking for the answer, but more how to get to the answer. Thank alot.

    A uniform ladder of mass m and length L leans at an angle theta.gif against a frictionless wall, Fig. 9-61. If the coefficient of static friction between the ladder and the ground is 0.43, what is the minimum angle at which the ladder will not slip?


    P.S. Whats theta mean? =X For whatever reason I never learned what it means in Physics 1.
    Last edited by a moderator: Apr 22, 2017
  2. jcsd
  3. Sep 25, 2006 #2

    Meir Achuz

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    Science Advisor
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    Gold Member

    The Greek letter theta is usually used for the angle in such problems.
    For your picture, the moment arm for the horizontal force at top of the ladder
    is given by L sin(theta). Draw a Free body diagram and work from that.
  4. Sep 25, 2006 #3

    Doc Al

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    Staff: Mentor

    As always, start by identifying all the forces acting on the ladder. Actually draw them on your diagram with proper labels.

    Once you've done that, apply the conditions for equilibrium, both translational and rotational.

    Hint: What's the maximum possible horizontal force that the floor can exert on the ladder?
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